Polyethyleneimine-Modified Polymer as an Efficient Palladium Scavenger and Effective Catalyst Support for a Functional Heterogeneous Palladium Catalyst
Polyethyleneimine-Modified Polymer as an Efficient Palladium Scavenger and Effective Catalyst Support for a Functional Heterogeneous Palladium Catalyst
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聚乙烯亚胺改性聚合物作为有效的钯清除剂和功能性多相钯催化剂的有效催化剂载体
DOI：
10.1021/acsomega.9b00707
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发表时间：
2019
期刊：
影响因子：
4.1
通讯作者：
Sajiki Hironao
中科院分区：
文献类型：
--
作者：
Yamada Tsuyoshi;Kobayashi Yutaka;Ito Naoya;Ichikawa Tomohiro;Park Kwihwan;Kunishima Kouki;Ueda Shun;Mizuno Masahiro;Adachi Tadashi;Sawama Yoshinari;Monguchi Yasunari;Sajiki Hironao
聚乙烯亚胺改性的聚合物，聚苯乙烯-二乙烯基苯基（TA）和聚甲基丙烯酸酯基聚合物（TAm），被用作钯清除剂以消除在钯/碳催化的Sonogashira型偶联反应之后的残留钯物种。由于TA和TAm都显示出对反应混合物中残留钯物种的相对有利的消除能力，因此TA和TAm对钯物种的亲和力被用作钯催化剂的载体。TAm负载的钯催化剂（Pd/TAm）比相应的TAs负载的钯催化剂（Pd/TAs）具有更好的化学选择性加氢性能。芳族苄基醚;芳香族和非芳香族N-Cbz;和芳族羰基在1- 5mol%的Pd/TAm的存在下在MeOH或2-PrOH中顺利氢化。而吗啉作为合适的催化剂毒物和溶剂，对芳香酮的加氢反应有选择性的抑制作用。此外，Pd/TAm催化的化学选择性加氢适用于连续流动反应。
The polyethyleneimine-modified polymers, polystyrene–divinylbenzene-based (TAs) and polymethacrylate-based polymers (TAm), were used as palladium scavengers to eliminate residual palladium species after palladium on carbon-catalyzed Sonogashira-type coupling reaction. Since both TAs and TAm indicated relatively favorable elimination abilities toward residual palladium species in the reaction mixture, the affinities of TAs and TAm for palladium species were used as supports for palladium catalysts. The TAm-supported palladium catalyst (Pd/TAm) indicated better catalyst properties for the chemoselective hydrogenation compared to those of the corresponding TAs-supported palladium catalyst (Pd/TAs). Aromatic benzyl ethers; aromatic and aliphaticN-Cbzs; and aromatic carbonyl groups were smoothly hydrogenated in the presence of 1–5 mol % of Pd/TAm in MeOH or 2-PrOH. In contrast, the hydrogenation of aromatic ketones was selectively suppressed in morpholine which act as appropriate catalyst poison and solvent. Furthermore, Pd/TAm-catalyzed chemoselective hydrogenation was applicable to continuous-flow reaction.